Ok, so I'm looking to upgrade my CPU from my current AMD Athlon II x4 645. The idea here is to be able to run two HD 6850's in crossfire, as I'm not sure this cpu would be up to the task. Hoping a CPU upgrade along with another 6850 to pair up with the one I have, would be enough to run BF3 on high/ultra at 1920x1080. Other games I play like WoW and Diablo 3 run fine at max settings with my current setup, but BF3, not so much.

I was going to go the Intel route as I know they currently make the ideal gaming cpu's, but I had my previous motherboard die on me and didn't have the cash to buy a whole new Mobo + cpu at that time, nor could I go that long without a computer. So I ended up buying a new am3+ board (Asus M5A97) just last week on sale for $89.

So with me being pretty much stuck choosing from a AMD cpu at the moment, what would be my best choice as a gaming CPU, one that would not bottleneck the two 6850's?

Ok, so I'm looking to upgrade my CPU from my current AMD Athlon II x4 645. The idea here is to be able to run two HD 6850's in crossfire, as I'm not sure this cpu would be up to the task. Hoping a CPU upgrade along with another 6850 to pair up with the one I have, would be enough to run BF3 on high/ultra at 1920x1080. Other games I play like WoW and Diablo 3 run fine at max settings with my current setup, but BF3, not so much.

I was going to go the Intel route as I know they currently make the ideal gaming cpu's, but I had my previous motherboard die on me and didn't have the cash to buy a whole new Mobo + cpu at that time, nor could I go that long without a computer. So I ended up buying a new am3+ board (Asus M5A97) just last week on sale for $89.

So with me being pretty much stuck choosing from a AMD cpu at the moment, what would be my best choice as a gaming CPU, one that would not bottleneck the two 6850's?

Crossfire with a 4x speed isn't worth it. You'd be better off selling the 6850 then investing the extra into a higher end GPU. You wouldn't need to upgrade the PSU then.

For CPU, yeah high end Phenom. Once you hit 3.6/3.7Ghz with the Phenoms the system really feels snappy.

But, have you tried clocking that 645? Those Athlons were not bad clockers. If your HSF is decent, could probably gain enough performance to hold you over until you could afford Intel or Piledriver...or whatever else comes up.

I run CF 5850s on my Athlon II X4 625 without a problem. but I only game @ 1440x900.

The difference between an Athlon II X4 and Phenom II X4 clock for clock is very similiar. I doubt the switch would justify the cost.

The Phenom II X6 is worth considering, but considering the Bulldozer X6 performs similarly in singethreaded apps, better in multithreaded apps, and overclocks further for the same price. Bulldozer X6 seems like a better choice.

The Phenom II X6 is worth considering, but considering the Bulldozer X6 performs similarly in singethreaded apps, better in multithreaded apps, and overclocks further for the same price. Bulldozer X6 seems like a better choice.

Tom's Hardware found that 2 HD6950's were bottlenecked by an FX-6100, granted the 6850's are lower end, it may not be the best solution. Plus games that are CPU-dependant do horribly on BD Setups due to their lower Per-Core Performance.

I think what I will do for now is invest in a CPU cooler (currently using stock HSF) and see what I can gain off this 645 with some OC'ing. I guess I should be trying to avoid sinking anymore money into an AMD build when Intel is clearly making the superior cpu's atm. I'm just a "right now" kinda guy and was looking for quick solution, hopefully I can OC this thing and see a difference.

Tom's Hardware found that 2 HD6950's were bottlenecked by an FX-6100, granted the 6850's are lower end, it may not be the best solution. Plus games that are CPU-dependant do horribly on BD Setups due to their lower Per-Core Performance.

Crossfire with a 4x speed isn't worth it. You'd be better off selling the 6850 then investing the extra into a higher end GPU. You wouldn't need to upgrade the PSU then.

For CPU, yeah high end Phenom. Once you hit 3.6/3.7Ghz with the Phenoms the system really feels snappy.

But, have you tried clocking that 645? Those Athlons were not bad clockers. If your HSF is decent, could probably gain enough performance to hold you over until you could afford Intel or Piledriver...or whatever else comes up.

And I agree with both of you to an extent. But, look at an overclock to reduce some scaling bottleneck, specifically NB frequency. Most of the 960T lineup when paired with a midrange air cooler will do 3.6Ghz/3.8-4 Turbo w/2.6-2.8Ghz NB.

And I agree with both of you to an extent. But, look at an overclock to reduce some scaling bottleneck, specifically NB frequency. Most of the 960T lineup when paired with a midrange air cooler will do 3.6Ghz/3.8-4 Turbo w/2.6-2.8Ghz NB.

But we are talking about +5% / -5% swing, it is pretty negligible difference. Typical Phenom II OC is about 3.8GHz area, Bulldozer a typical OC is 4.5GHz area. Even in single threaded Bulldozer would be miles faster with a 600-700MHZ OC handicap.

Tom's Hardware found that 2 HD6950's were bottlenecked by an FX-6100, granted the 6850's are lower end, it may not be the best solution. Plus games that are CPU-dependant do horribly on BD Setups due to their lower Per-Core Performance.

But what choice does the OP have? He only has two paths, Phenom II or Bulldozer. Both will to some degree will bottleneck performance. Single threaded performance and price are identical, the only thing that separates the two is maximum OC and this is where Bulldozer can be justified.